Transistor unit



G. W. S. FOGG TRANSISTOR UNIT Dec. 7, 1954 Filed June 5, 1953 INVENTOR.

Gm" e BY dim a 3 the strips on base is not unduly critical since man facturing tolerances are absorbed by the resilient nature of the ends of the various strips. Accurate spacing between knife edges 20 and 21 is achieved by the simple expedient of interposing the insulated spacer 22 between the bent-over extremities 18 and 19. The resulting unit is relatively rugged since its various metallic components arerigidly and securely anchored in base 10 and the semiconductive unit 29 is soldered or otherwise securely affixed to the end of strip 23 and firmly held against knife edges 20 and 21.

The transistor unit may be coated with a moisture proof coating such as a non-hygroscopic oil, and the unit may then be sealed in a suitable capsule. The knife edges 20 and 21 contact the edge of the crystal block at spaced points along the latter edge and may be sharpened, either mechanically or by means of an etching process to a width of the order of .0001".

The invention provides, therefore, an improved and rugged transistor unit that may be constructed simply and without the need for critical manual spacing and assembling of microscopic fine wire or cat-Whisker electrodes. The unit of the invention lends itself to mechanical formation of the various metallic strips by punching, shearing, die-cutting and the like, and the various strips may be assembled on the base and accurately placed in contact with the crystal without the need for delicate manual spacing and mounting operations.

Moreover, the unique construction of the improved transistor unit of the present invention permits the use of relatively large resilient metallic strips, thereby simplifying handling and facilitating production methods. The particular mounting of the resilient strips on the base provides uniform contact point pressure for each transistor unit and for successively produced units. This is because the contact pressure is established by the resilience of the strips themselves in conjunction with precisely located anchoring points for the strips on the base.

While a particular embodiment of the invention has been shown and described, modifications may be made and it is intended in the appended claims to cover all such modifications as fall within the true spirit and scope of the invention.

I claim:

1. A transistor unit including in combination, a flat insulating base member having a pair of ends and a centrally located longitudinal slot adjacent one of said ends, a pair of resilient electrically conductive strips mounted in spaced relation on a surface of said base and extending at an angle to said surface from one end of said base toward the other, said strips having end portions remote from said one end of said base extending inwardly toward one another and said end portions having bentover extremities extending downwardly toward said surface of said base, said extremities being spaced one from the other and terminating in a pair of spaced edges facing said base, a third resilient electrically conductive strip mounted on said base and extending along said base from said one end toward said other end intermediate said pair of strips, said third strip having a portion extending into and along said slot in said base and said portion of said third strip having an extremity extending upwardly toward the aforesaid edges of said extremities of said pair of strips at a selected angle thereto, and a block of semiconductive material affixed to said extremity of said portion of said third strip and having an edge in point contact with each of said edges of said extremities of said pair of strips.

2. A transistor unit including in combination, a base member, a pair of electrically conductive strips mounted on said base and inclined at an angle to a surface of said base, said strips having end portions extending downwardly toward said surface of said base in spaced and parallel relation, said end portions terminating in a pair of spaced edges, a third resilient electrically conductive strip mounted on said base and extending along said base, said third strip having an end portion extending upwardly toward the aforesaid pair of edges at a selected angle thereto, and a block of semi-conductive material affixed to said end portion of said third strip and having an edge in point contact with each of said pair of edges of said first-mentioned pair of strips.

3. A transistor unit including in combination, a base member having a longitudinal centrally located slot therein adjacent one end of said base, a pair of spaced electrically conductive resilient strips anchored to a surface of said base and extending toward said one end from said other end of said base at an angle to said surface, said strips having end portions extending downwardly toward said surface of said base in spaced parallel relation and said end portions terminating in a pair of spaced edges, a third resilient electrically conductive strip anchored to said surface of 'said base and extending along said base toward said one end from said other end of said base and extending into and along said slot, said third strip having an end portion extending upwardly toward the aforesaid pair of edges at a selected angle thereto, and a block of semi-conductive material afiixed to said end portion of said third strip and having an edge in resilient point contact with each of said pair of edges of said first-mentioned pair of strips.

4. A transistor unit including in combination, an insulating base member having a longitudinal centrally located slot therein at one end of said base, a pair of spaced parallel resilient metallic strips anchored to a surface of said base and extending toward said one end from the other end of said base at an angle to said surface, said strips having end portions extending inwardly toward one another and said end portions having bentover extremities extending downwardly toward said surface of said base, said extremities being spaced and parallel one to the other and terminating in a pair of spaced knife edges facing said base, a third resilient metallic strip anchored to said surface of said base and extending along said surface of said base toward said one end from said other end of said base and extending into and along said slot, said third strip having an end portion extending upwardly toward the aforesaid pair of edges at a selected angle thereto, and a block of semi-conductive material affixed to said end portion of said third strip and having an edge in resilient point contact with.

a central longitudinal slot, a pair of spaced parallel re-' silient metallic strips anchored to a surface of said base and extending from the other end of said base toward said one end at an angle to said surface, said strips having end portions extending inwardly toward one another and said end portions'having bent-over extremities extending downwardly toward said surface of said base, said extremities being parallel one to the other and terminating in a pair of spaced knife edges facing said base, an insulating spacer interposed between said extremities to insulate said strips one from the other and to space said edges by a selected amount, a third resilient metallic strip anchored to said surface of said base and extending along said base toward said one end thereof and into and along said slot, said third strip having an end portion extending upwardly toward the aforesaid pair of knife edges at a selected angle thereto, and a block of semi-conductive material afiixed to said end portion of said third strip and having an edge in resilient point contact with each of said pair of knife edges.

6. A transistor unit including-in combination, a base member, a pair of electrically conductive strips mounted on said base, said strips having adiacent end portions spaced from one another and terminating in a pair of spaced edges, a third resilient electrically conductive strip mounted on said base and having an end portion adjacent said pair of edges, and a block of semi-conductive material in contact with said third strip and having an edge in point contact with each of said pair of edges of said first-mentioned pair of strips.

References Cited in the file of this patent UNITED STATES PATENTS Number 

